In general, a speaker system disclosed in Patent Document 1 as below has been known as a technique for outputting data from an audio data transmitting device to an audio data reproducing speaker and reproducing the data.
In the speaker system, audio data is wirelessly transmitted from one audio data transmitting device to a plurality of audio data reproducing speakers. In this way, the speakers can reproduce different types of audio data.
However, data is transmitted from the audio data transmitting device to the audio data reproducing speakers, but it is difficult to transmit data from the audio data reproducing speakers to the audio data transmitting device.
Therefore, when the audio data transmitting device and the audio data reproducing speakers are provided in different rooms, it is difficult for the audio data reproducing speaker to change the volume or audio data to be reproduced, which is inconvenient for use.    PATENT DOCUMENT 1: Japanese Unexamined Patent Application, First Publication No. 2001-275194